#!/usr/bin/env python
# encoding: utf-8
'''
@author: KM
@license: (C) Copyright 2013-2017, Node Supply Chain Manager Corporation Limited.
@contact: yangkm601@gmail.com
@software: garner
@time: 2019/9/28
@url：https://leetcode-cn.com/problems/reverse-string/
@desc:
    
    344. 反转字符串

    编写一个函数，其作用是将输入的字符串反转过来。输入字符串以字符数组 char[] 的形式给出。

    不要给另外的数组分配额外的空间，你必须原地修改输入数组、使用 O(1) 的额外空间解决这一问题。

    你可以假设数组中的所有字符都是 ASCII 码表中的可打印字符。

    示例 1：

    输入：["h","e","l","l","o"]
    输出：["o","l","l","e","h"]
    示例 2：

    输入：["H","a","n","n","a","h"]
    输出：["h","a","n","n","a","H"]

'''
import math
class Solution:
    def reverseString(self, s):
        """
        :type s: List[str]
        :rtype: None Do not return anything, modify s in-place instead.
        """
        s_len = len(s)
        if s_len < 1 or s is None:
            return []
        
        left = 0
        right = s_len - 1

        while left < right:
            temp = s[left]
            s[left] = s[right]
            s[right] = temp
            left += 1
            right -= 1
        
        return s
        
  

if __name__ == "__main__":

    solution = Solution()

    print("--------1-------")
    nums1 = ["h","e","l","l","o"]
    res=solution.reverseString(nums1)
    print("res:{0}".format(res))

    print("--------2-------")
    nums1 = ["H","a","n","n","a","h"]
    res=solution.reverseString(nums1)
    print("res:{0}".format(res))

    